Brihat Samhita
प्रत्यर्कसंज्ञः परिधिस्तु तस्य त्रियोजनाभः परिघस्य पञ्च । षट्पञ्चदृश्यं परिवेषचक्रं दशामरेशस्य धनुर्विभाति ॥ ३०-३३ ॥
The halo called pratyarka (counter-sun) appears three yojanas in extent, that of the parigha is five. The circular halo (pariveṣa-cakra) is visible at a distance of six and five (i.e., eleven), and the rainbow of the lord of the gods (Indra) shines like a bow.
english translation
pratyarkasaMjJaH paridhistu tasya triyojanAbhaH parighasya paJca । SaTpaJcadRzyaM pariveSacakraM dazAmarezasya dhanurvibhAti ॥ 30-33 ॥
hk transliteration by Sanscript